The musculoskeletal system comprises bones, muscles, joints, ligaments, tendons, and bursae (see Introduction to Biology of the Musculoskeletal System Introduction to the Biology of the
Musculoskeletal System The musculoskeletal system provides form, stability, and movement to the human body. It consists of the body's bones (which make up the skeleton), muscles, tendons, ligaments, joints, cartilage... read more ). Any of these components can be injured or affected by a number of disorders. Some disorders affect primarily the joints (such as
osteoarthritis
Osteoarthritis (OA) Osteoarthritis is a chronic disorder that causes damage to the cartilage and surrounding tissues and is characterized by pain, stiffness, and loss of function. Arthritis due to damage of joint... read more Different diagnostic
tests are available to diagnose musculoskeletal disorders (see Tests for Musculoskeletal Disorders
Tests for Musculoskeletal Disorders A doctor can often diagnose a musculoskeletal disorder based on the history and the results of a physical examination. Laboratory tests, imaging tests, or other diagnostic procedures are sometimes... read more
During a musculoskeletal evaluation, doctors ask people about musculoskeletal symptoms but also look for other symptoms, such as fever, chills, weight loss, rash, eye pain or redness, and symptoms of heart, lung, and gastrointestinal disorders. These other symptoms may be caused by or associated with various musculoskeletal disorders. Doctors
also ask people to describe what the pain feels like, for example, whether it is sharp or dull or whether it is aching or burning. They need to know whether people feel the pain deep in a joint or whether other musculoskeletal structures seem to be affected by it. Knowing the type and location of the pain can help doctors figure out the cause.
Doctors also ask people to describe when they feel stiffness. In some joint disorders (such as rheumatoid arthritis
Rheumatoid Arthritis (RA) Rheumatoid arthritis is an inflammatory arthritis in which joints, usually including those of the hands and feet, are inflamed, resulting in swelling, pain, and often destruction of joints.... read more
People may have joint instability (for example, wobbliness or buckling of a joint), which suggests weakness of the ligaments or other structures that stabilize the joint. Buckling (when a joint gives out) occurs most often in the knee.
A doctor looks for certain things during a physical examination depending on what disorder or injury is suspected.
A doctor may feel (palpate) the surfaces of the bones and joints to detect any tenderness, warmth, fluid in the joints, or abnormal shape, particularly if a fracture, a tumor, or a bone infection
(osteomyelitis
Osteomyelitis Osteomyelitis is a bone infection usually caused by bacteria, mycobacteria, or fungi. Bacteria, mycobacteria, or fungi can infect bones by spreading through the bloodstream or, more often, by... read more ) is suspected. Compression fractures of the spine caused by
osteoporosis Osteoporosis Osteoporosis is
a condition in which a decrease in the density of bones weakens the bones, making breaks (fractures) likely. Aging, estrogen deficiency, low vitamin D or calcium intake, and... read more
Doctors also look for muscle enlargement (hypertrophy), which normally results from activities or exercises that repeatedly stress the muscle, such as weight lifting. However, when a person is ill, hypertrophy may result from one muscle working harder to compensate for the weakness of another. Muscles can also enlarge when normal muscle tissue is replaced
by abnormal tissue, which increases the size but not the strength of the muscle. Abnormal tissue can replace muscles in amyloidosis
Amyloidosis Amyloidosis is a rare disease in which abnormally folded proteins form amyloid fibrils that accumulate in various tissues and organs, sometimes leading to organ dysfunction, organ failure, and... read more
Doctors try to establish which (if any) muscles are weak and how weak they are. The muscles can be tested systematically, usually beginning with the face and neck, then the arms, and finally the legs. Normally, a person should be able to hold the arms extended, palms up, for one minute without their sagging, turning, or shaking. Downward drift of the arm with palms turning inward is a sign of weakness.
Strength is tested by pushing or pulling while the doctor pushes and pulls in the opposite direction. Strength is also tested by having the person perform certain maneuvers, such as walking on the heels and tiptoes or rising from a squatting position or getting up and down from a chair rapidly 10 times.
The doctor tests a person's active range of motion. The active range of motion is the maximum range through which people can move a joint by themselves. Limited active range of motion may indicate weakness, pain, or stiffness as well as mechanical abnormalities (such as scarring and swelling). The doctor then tests a person's passive range of motion. The passive range of motion is the maximum range through which the doctor can move the person's joint while the person is completely relaxed.
The doctor also checks muscle tone by moving the limb passively. Resistance to passive movement (called passive resistance) may be decreased when the nerve leading to the muscle is damaged. Resistance to such movement may be increased when the spinal cord or brain is damaged.
Doctors note which joints or limbs are affected. Finding a pattern of affected joints and limbs can help doctors figure out the cause.
Doctors also examine affected joints in more detail. For example, they examine the joints to determine whether fluid is in the joint (called a joint effusion). They may test specific active or passive motions. They may pull or apply force to see whether the joint is stable.
CLICK HERE FOR THE PROFESSIONAL VERSION
Copyright © 2022 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved.